Soil pipe vents

[David J]

Houses built between the Wars (and earlier) all had a visible soil pipe vent showing above the gutter.

Why are these not needed on modern houses?

DJ

[Tim S]

David J wibbled:

I've got vent pipes in my modern rented house - it's just as the pipes are all inside, the vent is well up the roofline and quite stubby as it's already 900mm above the window line.

I suppose there maybe be some scenarios where an AAV is OK, but my BCO told me I needed an vent, even with AAVs in case the sewer wanted to breath out. In fact, it does do this as I discovered when the warm weather came, with all the open ends in my house - wiffy...

[The Natural Philosopher]

They are, but they are generally tucked inside a *very* well ventilated loft.

Or exit high up on a gable.

[Tim S]

The Natural Philosopher wibbled:

Yuk. How the hell did that get to be approved under building regs, when you consider how fussy they are about other things?...

[The Natural Philosopher]

because of the high standards of insulation and airtightness, what happens in your loft is not really part of your concern these days ;-)

It is, essentially 'outside'..

[David J]

Thanks for introducing me to the AAV - which I had never heard of...

From reading installion instructions here about being 'boxed in':

that a householder will have little chance of inspecting if this AAV device is working properly - or is even there!

DJ

[Doctor Drivel]

The vent should terminate above the highest window with a cage on top. An AAV can be used or fit Hepworth HepVo traps in the basin, bath and sinks. These dry HepVo traps are AAV's themselves, so eliminating the need for one large AAV.

Eco homes do like to have penetrations of the building fabric, especially metal such as flues and overflow pipes. HepVo's eliminate the need for a soil pipe to penetrate the building fabric.

[Doctor Drivel]

Few will approve that.

[Tim S]

Doctor Drivel wibbled:

How does that vent +ve pressure?

[Doctor Drivel]

Every 5th house and end of line, needs an open vent. The rest can use an AAV or HepVO traps. The idea is to draw air into the sewer, the 5th house's stack allows air out.

[Tim S]

Doctor Drivel wibbled:

Yes - OK. I wonder what happens when the 5th house owner (times 2 or 3) looses theirs and sticks an AAV in :)

In teh olde days, they used to have open vent stacks in the roadway every now and then.

Cheers

Tim

[Hugo Nebula]

On Tue, 30 Jun 2009 10:41:16 +0100, a certain chimpanzee, Tim S randomly hit a keyboard and produced:

Not by _this_ BCO, it wasn't.

OP: vent stacks are still required. It's just that they're often boxed-in within the building with a stack passing through the roof to a ridge or tile vent, or an air-admittance valve. As a matter of fact, my 1999 semi has an external stack and an internal one.

[Tim S]

Hugo Nebula wibbled:

That concurs exactly with what my BCO said.

I can see how tile vents might give the illusion of not having a vent.

Cheers

Tim

[The Natural Philosopher]

It doesn't. Pure drivel, as usual.

[The Natural Philosopher]

Mine vents out through a gable as high as we could get it. BCO was happy.

I have to say however, that the other end of the drains go to a klargester, which isn't airtight ;-)

[Doctor Drivel]

This man is a lunatic.